xref: /freebsd/sys/dev/pci/pci_user.c (revision 1e413cf93298b5b97441a21d9a50fdcd0ee9945e)
1 /*-
2  * Copyright (c) 1997, Stefan Esser <se@freebsd.org>
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice unmodified, this list of conditions, and the following
10  *    disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25  */
26 
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29 
30 #include "opt_bus.h"	/* XXX trim includes */
31 #include "opt_compat.h"
32 
33 #include <sys/param.h>
34 #include <sys/systm.h>
35 #include <sys/malloc.h>
36 #include <sys/module.h>
37 #include <sys/linker.h>
38 #include <sys/fcntl.h>
39 #include <sys/conf.h>
40 #include <sys/kernel.h>
41 #include <sys/proc.h>
42 #include <sys/queue.h>
43 #include <sys/types.h>
44 
45 #include <vm/vm.h>
46 #include <vm/pmap.h>
47 #include <vm/vm_extern.h>
48 
49 #include <sys/bus.h>
50 #include <machine/bus.h>
51 #include <sys/rman.h>
52 #include <machine/resource.h>
53 
54 #include <sys/pciio.h>
55 #include <dev/pci/pcireg.h>
56 #include <dev/pci/pcivar.h>
57 
58 #include "pcib_if.h"
59 #include "pci_if.h"
60 
61 /*
62  * This is the user interface to PCI configuration space.
63  */
64 
65 static d_open_t 	pci_open;
66 static d_close_t	pci_close;
67 static int	pci_conf_match(struct pci_match_conf *matches, int num_matches,
68 			       struct pci_conf *match_buf);
69 static d_ioctl_t	pci_ioctl;
70 
71 struct cdevsw pcicdev = {
72 	.d_version =	D_VERSION,
73 	.d_flags =	D_NEEDGIANT,
74 	.d_open =	pci_open,
75 	.d_close =	pci_close,
76 	.d_ioctl =	pci_ioctl,
77 	.d_name =	"pci",
78 };
79 
80 static int
81 pci_open(struct cdev *dev, int oflags, int devtype, struct thread *td)
82 {
83 	int error;
84 
85 	if (oflags & FWRITE) {
86 		error = securelevel_gt(td->td_ucred, 0);
87 		if (error)
88 			return (error);
89 	}
90 
91 	return (0);
92 }
93 
94 static int
95 pci_close(struct cdev *dev, int flag, int devtype, struct thread *td)
96 {
97 	return 0;
98 }
99 
100 /*
101  * Match a single pci_conf structure against an array of pci_match_conf
102  * structures.  The first argument, 'matches', is an array of num_matches
103  * pci_match_conf structures.  match_buf is a pointer to the pci_conf
104  * structure that will be compared to every entry in the matches array.
105  * This function returns 1 on failure, 0 on success.
106  */
107 static int
108 pci_conf_match(struct pci_match_conf *matches, int num_matches,
109 	       struct pci_conf *match_buf)
110 {
111 	int i;
112 
113 	if ((matches == NULL) || (match_buf == NULL) || (num_matches <= 0))
114 		return(1);
115 
116 	for (i = 0; i < num_matches; i++) {
117 		/*
118 		 * I'm not sure why someone would do this...but...
119 		 */
120 		if (matches[i].flags == PCI_GETCONF_NO_MATCH)
121 			continue;
122 
123 		/*
124 		 * Look at each of the match flags.  If it's set, do the
125 		 * comparison.  If the comparison fails, we don't have a
126 		 * match, go on to the next item if there is one.
127 		 */
128 		if (((matches[i].flags & PCI_GETCONF_MATCH_DOMAIN) != 0)
129 		 && (match_buf->pc_sel.pc_domain !=
130 		 matches[i].pc_sel.pc_domain))
131 			continue;
132 
133 		if (((matches[i].flags & PCI_GETCONF_MATCH_BUS) != 0)
134 		 && (match_buf->pc_sel.pc_bus != matches[i].pc_sel.pc_bus))
135 			continue;
136 
137 		if (((matches[i].flags & PCI_GETCONF_MATCH_DEV) != 0)
138 		 && (match_buf->pc_sel.pc_dev != matches[i].pc_sel.pc_dev))
139 			continue;
140 
141 		if (((matches[i].flags & PCI_GETCONF_MATCH_FUNC) != 0)
142 		 && (match_buf->pc_sel.pc_func != matches[i].pc_sel.pc_func))
143 			continue;
144 
145 		if (((matches[i].flags & PCI_GETCONF_MATCH_VENDOR) != 0)
146 		 && (match_buf->pc_vendor != matches[i].pc_vendor))
147 			continue;
148 
149 		if (((matches[i].flags & PCI_GETCONF_MATCH_DEVICE) != 0)
150 		 && (match_buf->pc_device != matches[i].pc_device))
151 			continue;
152 
153 		if (((matches[i].flags & PCI_GETCONF_MATCH_CLASS) != 0)
154 		 && (match_buf->pc_class != matches[i].pc_class))
155 			continue;
156 
157 		if (((matches[i].flags & PCI_GETCONF_MATCH_UNIT) != 0)
158 		 && (match_buf->pd_unit != matches[i].pd_unit))
159 			continue;
160 
161 		if (((matches[i].flags & PCI_GETCONF_MATCH_NAME) != 0)
162 		 && (strncmp(matches[i].pd_name, match_buf->pd_name,
163 			     sizeof(match_buf->pd_name)) != 0))
164 			continue;
165 
166 		return(0);
167 	}
168 
169 	return(1);
170 }
171 
172 #if defined(COMPAT_FREEBSD4) || defined(COMPAT_FREEBSD5) || \
173     defined(COMPAT_FREEBSD6)
174 #define PRE7_COMPAT
175 
176 typedef enum {
177 	PCI_GETCONF_NO_MATCH_OLD	= 0x00,
178 	PCI_GETCONF_MATCH_BUS_OLD	= 0x01,
179 	PCI_GETCONF_MATCH_DEV_OLD	= 0x02,
180 	PCI_GETCONF_MATCH_FUNC_OLD	= 0x04,
181 	PCI_GETCONF_MATCH_NAME_OLD	= 0x08,
182 	PCI_GETCONF_MATCH_UNIT_OLD	= 0x10,
183 	PCI_GETCONF_MATCH_VENDOR_OLD	= 0x20,
184 	PCI_GETCONF_MATCH_DEVICE_OLD	= 0x40,
185 	PCI_GETCONF_MATCH_CLASS_OLD	= 0x80
186 } pci_getconf_flags_old;
187 
188 struct pcisel_old {
189 	u_int8_t	pc_bus;		/* bus number */
190 	u_int8_t	pc_dev;		/* device on this bus */
191 	u_int8_t	pc_func;	/* function on this device */
192 };
193 
194 struct pci_conf_old {
195 	struct pcisel_old pc_sel;	/* bus+slot+function */
196 	u_int8_t	pc_hdr;		/* PCI header type */
197 	u_int16_t	pc_subvendor;	/* card vendor ID */
198 	u_int16_t	pc_subdevice;	/* card device ID, assigned by
199 					   card vendor */
200 	u_int16_t	pc_vendor;	/* chip vendor ID */
201 	u_int16_t	pc_device;	/* chip device ID, assigned by
202 					   chip vendor */
203 	u_int8_t	pc_class;	/* chip PCI class */
204 	u_int8_t	pc_subclass;	/* chip PCI subclass */
205 	u_int8_t	pc_progif;	/* chip PCI programming interface */
206 	u_int8_t	pc_revid;	/* chip revision ID */
207 	char		pd_name[PCI_MAXNAMELEN + 1];  /* device name */
208 	u_long		pd_unit;	/* device unit number */
209 };
210 
211 struct pci_match_conf_old {
212 	struct pcisel_old	pc_sel;		/* bus+slot+function */
213 	char			pd_name[PCI_MAXNAMELEN + 1];  /* device name */
214 	u_long			pd_unit;	/* Unit number */
215 	u_int16_t		pc_vendor;	/* PCI Vendor ID */
216 	u_int16_t		pc_device;	/* PCI Device ID */
217 	u_int8_t		pc_class;	/* PCI class */
218 	pci_getconf_flags_old	flags;		/* Matching expression */
219 };
220 
221 struct pci_io_old {
222 	struct pcisel_old pi_sel;	/* device to operate on */
223 	int		pi_reg;		/* configuration register to examine */
224 	int		pi_width;	/* width (in bytes) of read or write */
225 	u_int32_t	pi_data;	/* data to write or result of read */
226 };
227 
228 #define	PCIOCGETCONF_OLD	_IOWR('p', 1, struct pci_conf_io)
229 #define	PCIOCREAD_OLD		_IOWR('p', 2, struct pci_io_old)
230 #define	PCIOCWRITE_OLD		_IOWR('p', 3, struct pci_io_old)
231 
232 static int	pci_conf_match_old(struct pci_match_conf_old *matches,
233 		    int num_matches, struct pci_conf *match_buf);
234 
235 static int
236 pci_conf_match_old(struct pci_match_conf_old *matches, int num_matches,
237     struct pci_conf *match_buf)
238 {
239 	int i;
240 
241 	if ((matches == NULL) || (match_buf == NULL) || (num_matches <= 0))
242 		return(1);
243 
244 	for (i = 0; i < num_matches; i++) {
245 		if (match_buf->pc_sel.pc_domain != 0)
246 			continue;
247 
248 		/*
249 		 * I'm not sure why someone would do this...but...
250 		 */
251 		if (matches[i].flags == PCI_GETCONF_NO_MATCH_OLD)
252 			continue;
253 
254 		/*
255 		 * Look at each of the match flags.  If it's set, do the
256 		 * comparison.  If the comparison fails, we don't have a
257 		 * match, go on to the next item if there is one.
258 		 */
259 		if (((matches[i].flags & PCI_GETCONF_MATCH_BUS_OLD) != 0)
260 		 && (match_buf->pc_sel.pc_bus != matches[i].pc_sel.pc_bus))
261 			continue;
262 
263 		if (((matches[i].flags & PCI_GETCONF_MATCH_DEV_OLD) != 0)
264 		 && (match_buf->pc_sel.pc_dev != matches[i].pc_sel.pc_dev))
265 			continue;
266 
267 		if (((matches[i].flags & PCI_GETCONF_MATCH_FUNC_OLD) != 0)
268 		 && (match_buf->pc_sel.pc_func != matches[i].pc_sel.pc_func))
269 			continue;
270 
271 		if (((matches[i].flags & PCI_GETCONF_MATCH_VENDOR_OLD) != 0)
272 		 && (match_buf->pc_vendor != matches[i].pc_vendor))
273 			continue;
274 
275 		if (((matches[i].flags & PCI_GETCONF_MATCH_DEVICE_OLD) != 0)
276 		 && (match_buf->pc_device != matches[i].pc_device))
277 			continue;
278 
279 		if (((matches[i].flags & PCI_GETCONF_MATCH_CLASS_OLD) != 0)
280 		 && (match_buf->pc_class != matches[i].pc_class))
281 			continue;
282 
283 		if (((matches[i].flags & PCI_GETCONF_MATCH_UNIT_OLD) != 0)
284 		 && (match_buf->pd_unit != matches[i].pd_unit))
285 			continue;
286 
287 		if (((matches[i].flags & PCI_GETCONF_MATCH_NAME_OLD) != 0)
288 		 && (strncmp(matches[i].pd_name, match_buf->pd_name,
289 			     sizeof(match_buf->pd_name)) != 0))
290 			continue;
291 
292 		return(0);
293 	}
294 
295 	return(1);
296 }
297 
298 #endif
299 
300 static int
301 pci_ioctl(struct cdev *dev, u_long cmd, caddr_t data, int flag, struct thread *td)
302 {
303 	device_t pcidev, brdev;
304 	void *confdata;
305 	const char *name;
306 	struct devlist *devlist_head;
307 	struct pci_conf_io *cio;
308 	struct pci_devinfo *dinfo;
309 	struct pci_io *io;
310 	struct pci_match_conf *pattern_buf;
311 	size_t confsz, iolen, pbufsz;
312 	int error, ionum, i, num_patterns;
313 #ifdef PRE7_COMPAT
314 	struct pci_conf_old conf_old;
315 	struct pci_io iodata;
316 	struct pci_io_old *io_old;
317 	struct pci_match_conf_old *pattern_buf_old;
318 
319 	io_old = NULL;
320 	pattern_buf_old = NULL;
321 
322 	if (!(flag & FWRITE) &&
323 	    (cmd != PCIOCGETCONF && cmd != PCIOCGETCONF_OLD))
324 		return EPERM;
325 #else
326 	if (!(flag & FWRITE) && cmd != PCIOCGETCONF)
327 		return EPERM;
328 #endif
329 
330 	switch(cmd) {
331 #ifdef PRE7_COMPAT
332 	case PCIOCGETCONF_OLD:
333 		/* FALLTHROUGH */
334 #endif
335 	case PCIOCGETCONF:
336 		cio = (struct pci_conf_io *)data;
337 
338 		pattern_buf = NULL;
339 		num_patterns = 0;
340 		dinfo = NULL;
341 
342 		cio->num_matches = 0;
343 
344 		/*
345 		 * If the user specified an offset into the device list,
346 		 * but the list has changed since they last called this
347 		 * ioctl, tell them that the list has changed.  They will
348 		 * have to get the list from the beginning.
349 		 */
350 		if ((cio->offset != 0)
351 		 && (cio->generation != pci_generation)){
352 			cio->status = PCI_GETCONF_LIST_CHANGED;
353 			error = 0;
354 			break;
355 		}
356 
357 		/*
358 		 * Check to see whether the user has asked for an offset
359 		 * past the end of our list.
360 		 */
361 		if (cio->offset >= pci_numdevs) {
362 			cio->status = PCI_GETCONF_LAST_DEVICE;
363 			error = 0;
364 			break;
365 		}
366 
367 		/* get the head of the device queue */
368 		devlist_head = &pci_devq;
369 
370 		/*
371 		 * Determine how much room we have for pci_conf structures.
372 		 * Round the user's buffer size down to the nearest
373 		 * multiple of sizeof(struct pci_conf) in case the user
374 		 * didn't specify a multiple of that size.
375 		 */
376 #ifdef PRE7_COMPAT
377 		if (cmd == PCIOCGETCONF_OLD)
378 			confsz = sizeof(struct pci_conf_old);
379 		else
380 #endif
381 			confsz = sizeof(struct pci_conf);
382 		iolen = min(cio->match_buf_len - (cio->match_buf_len % confsz),
383 		    pci_numdevs * confsz);
384 
385 		/*
386 		 * Since we know that iolen is a multiple of the size of
387 		 * the pciconf union, it's okay to do this.
388 		 */
389 		ionum = iolen / confsz;
390 
391 		/*
392 		 * If this test is true, the user wants the pci_conf
393 		 * structures returned to match the supplied entries.
394 		 */
395 		if ((cio->num_patterns > 0) && (cio->num_patterns < pci_numdevs)
396 		 && (cio->pat_buf_len > 0)) {
397 			/*
398 			 * pat_buf_len needs to be:
399 			 * num_patterns * sizeof(struct pci_match_conf)
400 			 * While it is certainly possible the user just
401 			 * allocated a large buffer, but set the number of
402 			 * matches correctly, it is far more likely that
403 			 * their kernel doesn't match the userland utility
404 			 * they're using.  It's also possible that the user
405 			 * forgot to initialize some variables.  Yes, this
406 			 * may be overly picky, but I hazard to guess that
407 			 * it's far more likely to just catch folks that
408 			 * updated their kernel but not their userland.
409 			 */
410 #ifdef PRE7_COMPAT
411 			if (cmd == PCIOCGETCONF_OLD)
412 				pbufsz = sizeof(struct pci_match_conf_old);
413 			else
414 #endif
415 				pbufsz = sizeof(struct pci_match_conf);
416 			if (cio->num_patterns * pbufsz != cio->pat_buf_len) {
417 				/* The user made a mistake, return an error. */
418 				cio->status = PCI_GETCONF_ERROR;
419 				error = EINVAL;
420 				break;
421 			}
422 
423 			/*
424 			 * Allocate a buffer to hold the patterns.
425 			 */
426 #ifdef PRE7_COMPAT
427 			if (cmd == PCIOCGETCONF_OLD) {
428 				pattern_buf_old = malloc(cio->pat_buf_len,
429 				    M_TEMP, M_WAITOK);
430 				error = copyin(cio->patterns,
431 				    pattern_buf_old, cio->pat_buf_len);
432 			} else
433 #endif
434 			{
435 				pattern_buf = malloc(cio->pat_buf_len, M_TEMP,
436 				    M_WAITOK);
437 				error = copyin(cio->patterns, pattern_buf,
438 				    cio->pat_buf_len);
439 			}
440 			if (error != 0) {
441 				error = EINVAL;
442 				goto getconfexit;
443 			}
444 			num_patterns = cio->num_patterns;
445 		} else if ((cio->num_patterns > 0)
446 			|| (cio->pat_buf_len > 0)) {
447 			/*
448 			 * The user made a mistake, spit out an error.
449 			 */
450 			cio->status = PCI_GETCONF_ERROR;
451 			error = EINVAL;
452 			break;
453 		}
454 
455 		/*
456 		 * Go through the list of devices and copy out the devices
457 		 * that match the user's criteria.
458 		 */
459 		for (cio->num_matches = 0, error = 0, i = 0,
460 		     dinfo = STAILQ_FIRST(devlist_head);
461 		     (dinfo != NULL) && (cio->num_matches < ionum)
462 		     && (error == 0) && (i < pci_numdevs) && (dinfo != NULL);
463 		     dinfo = STAILQ_NEXT(dinfo, pci_links), i++) {
464 
465 			if (i < cio->offset)
466 				continue;
467 
468 			/* Populate pd_name and pd_unit */
469 			name = NULL;
470 			if (dinfo->cfg.dev && dinfo->conf.pd_name[0] == '\0')
471 				name = device_get_name(dinfo->cfg.dev);
472 			if (name) {
473 				strncpy(dinfo->conf.pd_name, name,
474 					sizeof(dinfo->conf.pd_name));
475 				dinfo->conf.pd_name[PCI_MAXNAMELEN] = 0;
476 				dinfo->conf.pd_unit =
477 					device_get_unit(dinfo->cfg.dev);
478 			}
479 
480 #ifdef PRE7_COMPAT
481 			if ((cmd == PCIOCGETCONF_OLD &&
482 			    (pattern_buf_old == NULL ||
483 			    pci_conf_match_old(pattern_buf_old, num_patterns,
484 			    &dinfo->conf) == 0)) ||
485 			    (cmd == PCIOCGETCONF &&
486 			    (pattern_buf == NULL ||
487 			    pci_conf_match(pattern_buf, num_patterns,
488 			    &dinfo->conf) == 0))) {
489 #else
490 			if (pattern_buf == NULL ||
491 			    pci_conf_match(pattern_buf, num_patterns,
492 			    &dinfo->conf) == 0) {
493 #endif
494 				/*
495 				 * If we've filled up the user's buffer,
496 				 * break out at this point.  Since we've
497 				 * got a match here, we'll pick right back
498 				 * up at the matching entry.  We can also
499 				 * tell the user that there are more matches
500 				 * left.
501 				 */
502 				if (cio->num_matches >= ionum)
503 					break;
504 
505 #ifdef PRE7_COMPAT
506 				if (cmd == PCIOCGETCONF_OLD) {
507 					conf_old.pc_sel.pc_bus =
508 					    dinfo->conf.pc_sel.pc_bus;
509 					conf_old.pc_sel.pc_dev =
510 					    dinfo->conf.pc_sel.pc_dev;
511 					conf_old.pc_sel.pc_func =
512 					    dinfo->conf.pc_sel.pc_func;
513 					conf_old.pc_hdr = dinfo->conf.pc_hdr;
514 					conf_old.pc_subvendor =
515 					    dinfo->conf.pc_subvendor;
516 					conf_old.pc_subdevice =
517 					    dinfo->conf.pc_subdevice;
518 					conf_old.pc_vendor =
519 					    dinfo->conf.pc_vendor;
520 					conf_old.pc_device =
521 					    dinfo->conf.pc_device;
522 					conf_old.pc_class =
523 					    dinfo->conf.pc_class;
524 					conf_old.pc_subclass =
525 					    dinfo->conf.pc_subclass;
526 					conf_old.pc_progif =
527 					    dinfo->conf.pc_progif;
528 					conf_old.pc_revid =
529 					    dinfo->conf.pc_revid;
530 					strncpy(conf_old.pd_name,
531 					    dinfo->conf.pd_name,
532 					    sizeof(conf_old.pd_name));
533 					conf_old.pd_name[PCI_MAXNAMELEN] = 0;
534 					conf_old.pd_unit =
535 					    dinfo->conf.pd_unit;
536 					confdata = &conf_old;
537 				} else
538 #endif
539 					confdata = &dinfo->conf;
540 				/* Only if we can copy it out do we count it. */
541 				if (!(error = copyout(confdata,
542 				    (caddr_t)cio->matches +
543 				    confsz * cio->num_matches, confsz)))
544 					cio->num_matches++;
545 			}
546 		}
547 
548 		/*
549 		 * Set the pointer into the list, so if the user is getting
550 		 * n records at a time, where n < pci_numdevs,
551 		 */
552 		cio->offset = i;
553 
554 		/*
555 		 * Set the generation, the user will need this if they make
556 		 * another ioctl call with offset != 0.
557 		 */
558 		cio->generation = pci_generation;
559 
560 		/*
561 		 * If this is the last device, inform the user so he won't
562 		 * bother asking for more devices.  If dinfo isn't NULL, we
563 		 * know that there are more matches in the list because of
564 		 * the way the traversal is done.
565 		 */
566 		if (dinfo == NULL)
567 			cio->status = PCI_GETCONF_LAST_DEVICE;
568 		else
569 			cio->status = PCI_GETCONF_MORE_DEVS;
570 
571 getconfexit:
572 		if (pattern_buf != NULL)
573 			free(pattern_buf, M_TEMP);
574 #ifdef PRE7_COMPAT
575 		if (pattern_buf_old != NULL)
576 			free(pattern_buf_old, M_TEMP);
577 #endif
578 
579 		break;
580 
581 #ifdef PRE7_COMPAT
582 	case PCIOCREAD_OLD:
583 	case PCIOCWRITE_OLD:
584 		io_old = (struct pci_io_old *)data;
585 		iodata.pi_sel.pc_domain = 0;
586 		iodata.pi_sel.pc_bus = io_old->pi_sel.pc_bus;
587 		iodata.pi_sel.pc_dev = io_old->pi_sel.pc_dev;
588 		iodata.pi_sel.pc_func = io_old->pi_sel.pc_func;
589 		iodata.pi_reg = io_old->pi_reg;
590 		iodata.pi_width = io_old->pi_width;
591 		iodata.pi_data = io_old->pi_data;
592 		data = (caddr_t)&iodata;
593 		/* FALLTHROUGH */
594 #endif
595 	case PCIOCREAD:
596 	case PCIOCWRITE:
597 		io = (struct pci_io *)data;
598 		switch(io->pi_width) {
599 		case 4:
600 		case 2:
601 		case 1:
602 			/* Make sure register is in bounds and aligned. */
603 			if (io->pi_reg < 0 ||
604 			    io->pi_reg + io->pi_width > PCI_REGMAX + 1 ||
605 			    io->pi_reg & (io->pi_width - 1)) {
606 				error = EINVAL;
607 				break;
608 			}
609 			/*
610 			 * Assume that the user-level bus number is
611 			 * in fact the physical PCI bus number.
612 			 * Look up the grandparent, i.e. the bridge device,
613 			 * so that we can issue configuration space cycles.
614 			 */
615 			pcidev = pci_find_dbsf(io->pi_sel.pc_domain,
616 			    io->pi_sel.pc_bus, io->pi_sel.pc_dev,
617 			    io->pi_sel.pc_func);
618 			if (pcidev) {
619 				brdev = device_get_parent(
620 				    device_get_parent(pcidev));
621 
622 #ifdef PRE7_COMPAT
623 				if (cmd == PCIOCWRITE || cmd == PCIOCWRITE_OLD)
624 #else
625 				if (cmd == PCIOCWRITE)
626 #endif
627 					PCIB_WRITE_CONFIG(brdev,
628 							  io->pi_sel.pc_bus,
629 							  io->pi_sel.pc_dev,
630 							  io->pi_sel.pc_func,
631 							  io->pi_reg,
632 							  io->pi_data,
633 							  io->pi_width);
634 #ifdef PRE7_COMPAT
635 				else if (cmd == PCIOCREAD_OLD)
636 					io_old->pi_data =
637 						PCIB_READ_CONFIG(brdev,
638 							  io->pi_sel.pc_bus,
639 							  io->pi_sel.pc_dev,
640 							  io->pi_sel.pc_func,
641 							  io->pi_reg,
642 							  io->pi_width);
643 #endif
644 				else
645 					io->pi_data =
646 						PCIB_READ_CONFIG(brdev,
647 							  io->pi_sel.pc_bus,
648 							  io->pi_sel.pc_dev,
649 							  io->pi_sel.pc_func,
650 							  io->pi_reg,
651 							  io->pi_width);
652 				error = 0;
653 			} else {
654 #ifdef COMPAT_FREEBSD4
655 				if (cmd == PCIOCREAD_OLD) {
656 					io_old->pi_data = -1;
657 					error = 0;
658 				} else
659 #endif
660 					error = ENODEV;
661 			}
662 			break;
663 		default:
664 			error = EINVAL;
665 			break;
666 		}
667 		break;
668 
669 	default:
670 		error = ENOTTY;
671 		break;
672 	}
673 
674 	return (error);
675 }
676